Metal alloys and process of producing the same



Patented Mar. 1, 1932 1,847,941

UNITED, STATES PATENT oi-"iuca METAL ALLOYS AND rnocnss F rnonueme m inDrawing. Application med January 22, 1926; serial are. 03,109.

This invention relates to improvements in with this indium coating isthen heatalloys or intimate mixtures of metals hereined in a furnace ata temperature about after called alloys, for brevity, and to the meltingpoint of the indium 5 processes of producing the same. This heat n iscontinued until the indium The alloy to which this invention has refhasbeen d1 used thru and therefore intlmateerence is one comprising, andreferably conly mixed with the silver. The alloyor 1nt1- sisting of,silver and indium. uch alloy may mate mlxture is then removed from thefurbe either raw material from which to make mace and allowed to c0ol.The heatin of the finished articles or be the coating of a plated ve wth th s Ind um coat ngi may con- 10 article. ducted in the presence of ahy rogen atmos- Preferably, the silver content will predomphe ev inatein the alloy and the indium content be n the productlon of the coatingof a plated such as to render the surface of the alloy tarartlcle Wproceed as follows: nish resistant; the silver content for sterling T eor base metal to be coated has 5 or coin silver standards for example,bein filSddGPOSltfBd upon itbyelectro-depos tion a about or more. coatinof silver; at coatlng ofindium is then The alloy may contain additionalingre- P to thls: fJ] a g, pr ferably, dients to the silver and indium,if desired for a y l t opos .Anothel coatmg certain purposes, but whentarnish resistf 511%! 18 coated y -deposlance is desired the addedingredient or ingretlon upon the indium coatmg. The base w1th 7o dientsmust be such as not to neutralize the thesethree coatings is then heatedas before tarnish resisting or shielding action of the described 1nprocess 2: Silver is surface indium, I coated, as for example, byelectro-deposition,-,

As above indicated, the alloy may be in the ith the desired. or requiredquantity of inform of raw material from which .to make dium, and thesilver with this indium coat- 75 finished products, or it may be thecoating mg is then heated in;a furnace. at a temperaof a plated article.In the production of the ture about the melting point of the indiumformer we may proceed according to the fol- (155 0.). This heating iscontinued until lowing methods or processes; the indium has beendiflused thru and there- 30 1. We introduce into a quartz tube a preforeintimately mixed with the silver. The 60.

' determined quantity of silver and also a prealloy or intlmate mixtureis then removed determined quantity of indium. The tube is from thefurnace and allowed to cool. The evacuated and sealed 011', then thetube with heating of the silver with this indium coatcontents is heatedin a furnace at a temperaing may be conducted in the presence of a 35ture above the melting point of silver 960 hydrogen atmosphere. Suchheating being 0.). The heating is continued until the two continueduntil the middle coating of indium metals are intimately mixed. Themetals thus has been properly difiused thru the coatings mixed, oralloys, are then removed and perof silver. The plated article is thenremoved mitted to cool. The quantity of indium used from the furnace andsubjected to the usual may vary from a fraction of 1% to 25%relafinishing processes of polishing, etc. tively to the total-silverand indium. The If desired the initial or first coating of quality oftarnish resistance of the alloy insilver may be omitted and the firstcoating creasing as the quantity of indium is inapplied to the base orbase metalbeof indium creased. followed by a. coating of silver, but weprefer 4 Ijorsterhngor com standards the quantity to begin with aninitial coating of silver. of indium used should not exceed 10% and itIt will also be understood. that instead of may less. using acoating ofsilver, a coating of indium 2. Silver is surfacecoated, as for example,and a coating of silver or a coating or indium' byclectro deposition,with the desired or reand a coating of silver, additional alternating 10 quired quantity of indium, and the silver coatings of these twometalsmaybeused.

it What is claimed is:

1. An alloy or intimate mixture consisting of silver and a measurableamount of indium, with the silver content predominating.

5 2. Analloy or intimate mixture consisting of silver and a measurableamount of indium, with the silver content constituting about 90% or moreof the combined silver and indium.

3. A tarnish-resisting alloy or intimate mixture comprising silver andindium, with the silver content predominating and the indium insufiicient quantity to give protection to the alloy or mixture againsttarnish.

4. A tarnish-resisting alloy or intimate mixture comprising silver andindium, with the silver content constituting about 90% or more of thecombined silver and indium and with the indium in sufficient quantity togive 2 protection to the alloy or mixture against tarnish.

5. The process of producing an alloy or intimate mixture comprisingsilver and indium which consists in uniting layers of'silver and indiumand difiusing the latter through the former at a suitable temperature.

6'. he process of producing an alloy or intimate mixture consisting ofsilver and indium which consists in uniting layers of silver and indiumand then diffusing the latter through the former at "a suitabletemperature.

7. I he process of producing a tarnish-resisting alloy or intimatemixture comprising silver and indium which consists in uniting layers ofsilver and indium and then diffusing the latter through the former at asuitable temperature. i 1

8. An alloy or intimate mixture consisting of silver and indium, withthe silver content 40. predominating.

9.- A tarnish-resisting alloy or intimate mixture consisting of silverand indium, with the silver content predominating,

In testimony whereof, we have hereunto set our hands.

- DANIEL GRAY.

RICHARD O. BAILEY. I WILLIAM S. MURRAY.

